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Investigation of the kinetic mechanism of the demanganization reaction between carbon-saturated liquid iron and CaF2–CaO–SiO2-based slags

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International Journal of Minerals,Metallurgy and Materials 2018年第4期25卷 399-404页

作者： sheng-chao Duan Chuang Li Han-jie Guo Jing Guo Shao-wei Han wen-sheng yang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing 100083 China China Metallurgical Planning and Research Institute Beijing 100711 China

The demanganization reaction kinetics of carbon-saturated liquid iron with an eight-component slag consisting of CaO–SiO2–MgO–FeO–MnO–Al2O3–TiO2–CaF2 was investigated at 1553, 1623, and 1673 K in this study. The rate-controlling step（RCS） for the demanganization reaction with regard to the hot metal pretreatment conditions was studied via kinetics analysis based on the fundamental equation of heterogeneous reaction kinetics. From the temperature dependence of the mass transfer coefficient of a transition-metal oxide（MnO）, the apparent activation energy of the demanganization reaction was estimated to be 189.46 kJ·mol^–1 in the current study, which indicated that the mass transfer of MnO in the molten slag controlled the overall rate of the demanganization reaction. The calculated apparent activation energy was slightly lower than the values reported in the literature for mass transfer in a slag phase. This difference was attributed to an increase in the ＂specific reaction interface＂（SRI） value, either as a result of turbulence at the reaction interface or a decrease of the absolute amount of slag phase during sampling, and to the addition of calcium fluoride to the slag.

关键词： demoaganization reaction kinetics reaction mechanism kinetic model rate-controlling step mass transfer coefficient apparent activation energy

Simulation study of blast fume diffusion characters of driving face

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Journal of Coal Science & Engineering(China) 2011年第1期17卷 47-51页

作者： LU wen-sheng HE Lei yang Peng Key Lab of High-Efficiency Mining and Safety of the Metal Mines Ministry of Education University of Science and TechnologyBeijing Beijing 100083 China

Based on FLUENT software, studied the blast fume diffusion characteristics of a driving face under 8 situations, and analyzed the influence to fume diffusion of different drift length and different ventilation pipe outlet positions. Through regression analysis, functions of ventilation time to the drift length and ventilation pipe outlet position was obtained.

关键词： ventilation numerical simulation driving face blast fume

Predictors of non-response to cardiac resynchronization therapy implantation in patients with class Ⅰ indications: the markedly dilated left ventricular end-diastolic dimension and the presence of fragmented QRS

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Journal of Geriatric Cardiology 2019年第7期16卷 514-521页

作者： Yi-Ran HU Wei HUA sheng-wen yang Min GU Hong-Xia NIU Li-Gang DING Jing WANG Ran JING Xiao-Han FAN Shu ZHANG State Key Laboratory of Cardiovascular Disease Arrhythmia CenterFuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Background Cardiac resynchronization therapy(CRT)is a highly effective treatment in patients with a class I ***,a small proportion of the strictly selected patients still fail to *** study was designed to identify predictors of non-response in patients with class I indications for CRT and determine the non-response probability of the *** A total of 296 consecutive patients with a class I recommendation received CRT from January 2009 to January 2017 were retrospectively *** logistic regression analysis was performed to identify predictors for non-response(defined as cardiac death,heart transplantation,or HF hospitalization during 1-year follow-up).Results Among 296 patients,30(10.1%)met *** analysis demonstrated that non-response to CRT was associated with a fragmented QRS(odd ratio(OR)=2.86,95%CI:1.14–7.12;P=0.025)and left ventricular end-diastolic dimension(LVEDD)≥77 mm(OR=3.02,95%CI:1.17–7.82;P=0.022).Patients with both of the predictors had a non-response probability of 46.2%(95%CI:19.1%–73.3%).Conclusion In patients with left bundle branch block and wider QRS duration,the proportion of non-response to CRT is not low in real *** presence of the dilated LVEDD or fragmented QRS is a strong predictor of non-response to *** probability of non-response in the patients with the two predictors was 46.2%.

关键词： Cardiac resynchronization therapy Class I indication Non-response Predictors

Determination of thermodynamic properties in full composition range of Ti-Al binary melts based on atom and molecule coexistence theory

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Transactions of Nonferrous Metals Society of China 2018年第6期28卷 1256-1264页

作者： sheng-chao DUAN Xiao SHI wen-sheng yang Han-jie GUO Jing GUO School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Special Melting and Preparation of High-end Metal Materials University of Science and Technology BeijingBeijing 100083China

The results of predicting thermodynamic properties in the full composition range of Ti-Al binary melts in a temperature range from 1973 to 2273 K were obtained by coupling with the developed thermodynamic model for calculating mass action concentration N_i of structural units in Ti-Al system based on the atom and molecule coexistence theory（AMCT）. Temperature dependence of the activity coefficients of Ti and Al in natural logarithmic form in the infinitely dilute solution（0x_（Ti）0.01） of Ti-Al binary melts was also determined from the calculated activity coefficients of Ti and Al at temperatures of 1973, 2073, 2173, and 2273 K. The standard molar Gibbs free energy change of dissolving pure liquid element i（l） for forming 1%（mass fraction） element i in Ti-Al binary melts further was deduced. With the aid of this model, meanwhile, the determined excess thermodynamic properties, such as the excess molar mixing Gibbs free energy/entropy/enthalpy were also calculated.

关键词： Ti-Al binary system Ti Al activity coefficient thermodynamic model mass action concentration atom and molecule coexistence theory

Nanostructured Columns from Self-assemblyof Complementary Molecular Components

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Chemical Research in Chinese Universities 2001年第2期17卷 193-197页

作者： yang wen-sheng ,yang Bai-quan, JIANG Yue-shun and LI Tie-jin (Department of Chemistry, Jilin University, Changchun, 130023, P. R. China) LIU Ya-Juan (Institute of Information Technology, Jilin Agriculture University, Changchun, 130118, P. R. China) Jilin Univ Dept Chem Changchun 130023 Peoples R China Jilin Agr Univ Inst Informat Technol Changchun 130118 Peoples R China

Nanostructured columns with a length about several tens of micrometer and a diameter of about 80 nm were obtained by molecular recognition directed self-assembly of a pair of comple- mentary molecular components, 4-amino-2 , 6-didodecylamino-1 , 3, 5-triazine(M) and 5- (4-dode- cyloxybenzylidene )-(1H, 3H)-2, 4, 6-pyrimidinetrione (B) in chloroform. In this system, with positive cooperativity, π-aromatic stacking and van der Waals interactions as well as hydrogen bonds cause the formation of the nanocolumns.

关键词： Nanocolumn Self-assembly π-aromatic stacking Molecular recognition

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碲镉汞模拟探测器量子效率定标方法

光子学报 2017年第11期46卷 106-112页

作者：盛文阳李健军夏茂鹏郑小兵中国科学院通用光学定标与表征技术重点实验室合肥230031 中国科学技术大学合肥230026

为测量红外模拟探测器量子效率,搭建了基于参量下转换效应的测量系统.利用光学参量振荡器调谐输出的2 576.5nm波长连续激光束作为泵浦源、ZnGeP2晶体作为非线性晶体,获取了3.42μm和10.4μm的相关光子对.实验中通过将采集到的两个通道... 详细信息

为测量红外模拟探测器量子效率,搭建了基于参量下转换效应的测量系统.利用光学参量振荡器调谐输出的2 576.5nm波长连续激光束作为泵浦源、ZnGeP2晶体作为非线性晶体,获取了3.42μm和10.4μm的相关光子对.实验中通过将采集到的两个通道的光电流/电压信号转换为等效光子计数,并利用两光路平衡测量的方法对每个模式的平均光子计数进行校正,实现了碲镉汞红外模拟探测器在10.4μm处的绝对功率响应度定标,得到了相对合成不确定度优于4.53%的定标结果.

关键词：遥感参量下转换相关光子模拟探测器量子效率定标

Non-contact and Automatic Measurement of 2D Size with CCD Matrix and Computer System

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Semiconductor Photonics and Technology 2003年第3期9卷 189-192页

作者： ZHANG Ye, WANG wen-sheng, GUO yang-xue, SONG Hui-ying (College of Photoelectr.Eng.,Changchun University of Science and Technology,Changchun 130022,CHN) College of Photoelectr. Eng. Changchun University of Science and Technology Changchun 130022

A measurement system with the CCD matrix and computer system is designed to test the 2D size of any shape workpieces automatically. In addition, the system adopts the method of the relative measurement which increases the precision and the *** importantly,the precision cant be changed with the conditions of the temperature and air *** experiments show that the relative precision of 0.002 9 and the absolute precision of 2.97 μm are obtained. The instrument may be used in the product line and make the testing on line possible.

关键词： CCD matrix photographic objective computer

基于相关光子多模式相关性的InSb模拟探测器定标方法

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物理学报 2015年第24期64卷 119-125页

作者：夏茂鹏李健军高冬阳胡友勃盛文阳庞伟伟郑小兵中国科学院通用光学定标与表征技术重点实验室合肥230031

利用基于参量下转换产生的相关光子可以实现"无溯源"的绝对定标.将该方法推广应用于模拟探测器定标的过程中,获取两路模拟光电流信号的有效相关信息是主要难点.在相关光子的多模式相关性理论模型的基础上,提出了一种新的光电流处理方案... 详细信息

利用基于参量下转换产生的相关光子可以实现"无溯源"的绝对定标.将该方法推广应用于模拟探测器定标的过程中,获取两路模拟光电流信号的有效相关信息是主要难点.在相关光子的多模式相关性理论模型的基础上,提出了一种新的光电流处理方案.通过将某一时刻采集到的光电流所包含的电荷量转换为等效光子计数,采用双光路平衡探测和双通道数据波动校正的技术思路,开展了红外模拟探测器量子效率定标验证实验研究.利用532 nm单波长激光器为抽运源、PPLN晶体为非线性晶体,在25?C工作温度下获取了631和3390 nm的相关光子对,定标了In Sb红外模拟探测器在3390 nm处的绝对功率响应度.结果表明,对In Sb模拟探测器的合成不确定度为7.785%.根据量子效率与绝对功率响应度之间的函数关系,所得定标结果与国内计量单位的校准结果的相对偏差为3.6%.利用多模式相关性在模拟信号下实现红外模拟探测器的绝对功率响应度定标在国际上暂无此方面的报道,该方法验证了应用多模式相关性理论开展模拟探测器定标方法的可行性,对于探索基于相关光子的定标技术和拓宽辐射定标应用领域具有重要意义.

关键词：定标参量下转换模拟定标 In Sb红外探测器

Circulating miR-519e * as a new biomarker of acute myocardial infarction

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Circulating miR-519e * as a new biomarker of acute myocardia...